traffic any more. Therefore, in this paper, a marine traffic situation complexity model, which is based on the ... can't fully represent the traffic complicacy, it is also.
MATEC Web of Conferences 68, 15002 (2016)
DOI: 10.1051/matecconf/20166815002
ICIEA 2016
Modelling of the Marine Traffic Situation Complexity 1,2
Xiaoqiao Geng , Liang Huang
1, 2
1, 2
, Yuanqiao Wen
and Chunhui Zhou
1, 2
1
School of navigation, Wuhan University of Technology, Wuhan, 430063, China Hubei Key Laboratory of Inland Shipping Technology, Wuhan, 430063, China
2
Abstract. With the growth of traffic density, traditional collision risk models cannot thoroughly describe the complex traffic any more. Therefore, in this paper, a marine traffic situation complexity model, which is based on the relationship between ships, is introduced to metric the complexity of vessel traffic. Firstly, traffic density factor and traffic conflict factors are considered to construct the traffic unit complexity model, reflecting the traffic complexity and traffic characteristics; Secondly, by extending the traffic unit complexity model into the own-ship complexity model, the influences of the positions of other ship on the complexity spatial distribution are analysed; Finally, two scenarios are imported to validate the availability of the complexity model. The verification results show that the complexity can respond to different route structures and traffic situations sensitively.
1 Introduction The tendencies of the marine traffic density increasing has increased the difficulty of water traffic management. To make up for the limitations of traditional risk models that most of them only use DCPA and TCPA as the evaluation indicators [1], which only measure the spatial relationships and urgency degree of two ships, without considering their relative position, marine traffic complexity is introduced to describe the complicated situation of marine traffic. There have been some progresses in complexity researching in the fields of air transportation and road traffic: One the one hand, researchers use linear[2] and nonlinear[3] modelling methods to construct the dynamic density model of airspace complexity.[4] On the other hand, researchers think complexity can be considered as the subjective description of traffic situation using intrinsic properties[5]. Airspace complexity model was established based on the coupling relationship of traffic flow.[6,7] Therefore, it is needed to research into the traffic flow complexity in the marine traffic field. In this paper, intrinsic properties complexity is used to research the marine traffic situation, and two complexity factors of traffic density and traffic conflict are proposed to construct the complexity model, then verification is made.
Therefore, researches on the traffic situation complexity can be carried from vessel traffic density and geometrical relationships between vessels. In the following research, the traffic relationship unit VCij (Vessel Couple) constructed by two ships of i and j is defined. 2.1 Influential factors of traffic density Definition1: Traffic complexity directly caused by the traffic density is called as complicacy I CFirst_ij. Traffic density described by the ships amount in unit water area can’t fully represent the traffic complicacy, it is also related with the space among ships and the distribution of ships. Definition2: The traffic density in the traffic unit is related with the relative distance of ships, and it equals the value of complicacy I CFirst_ij . Then there is: CFirst_ij
In Eq.1,
e e
Dij / Riij
, Dij Rij
(1)
, Dij
